1. Field of the Invention
The present invention relates to a method of processing a saponin-containing plant such as Panax notoginseng into a high sapogenin content composition, which contains the sapogenin in a larger amount. Namely, the present invention relates to a method for producing a high sapogenin content composition using a saponin-containing plant as a raw material.
2. Description of the Related Art
Many plants used for herbal medicines are utilized after processed for the purpose of reducing toxicity, improving preserving properties, and enhancing medicinal effect. As to ginsengs, “Ginseng Radix Rubra” obtained by steaming a ginseng with boiling water, and the like are known as processed ginsengs. For example, a method for producing a processed ginseng for enhancing medicinal effect has been reported, and a method of further increasing a content of a saponin which is a pharmacologically-active component of Ginseng Radix Rubra is disclosed in Japanese Patent Application Laid-Open (JP-A) No. 11-501322.
It has been known that a saponin which is glycoside is poorly absorbed inside of body, but a sapogenin, which is obtained by hydrolyzing a saponin so as to separate a saccharide portion of the saponin therefrom, is absorbed well inside of body, and that the sapogenin exhibits a physiological activity such as an anticancer activity stronger than the saponin. A method of processing a ginseng is disclosed, for example, in International Publication No. WO 2005/030235 and this method aims to produce an extract of the ginseng. However, in this method, although the operation is complicated, the amount of a sapogenin is not sufficiently produced, and there are problems that the resultant product is poor in safety and taste for using as a processed ginseng.
Therefore, in the present circumstances, a method of easily producing a high sapogenin content composition, which contains a large amount of a sapogenin and is excellent in taste and safety, using a saponin-containing plant as a raw material, has not been developed yet.